Eleocharis flavescens (Poir.) Urban

yellow spikesedge

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New England Distribution

Adapted from BONAP data

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North America Distribution

Adapted from BONAP data

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Facts About

Yellow spikesedge is a common plant of shorelines, marshes, river shores and peat swamps, found in all New England states. It is called "yellow" spikesedge for its straw-colored achenes. These have long bristles, which give the whole spike a "curly" appearance. It propagates vegeatatively on skinny rhizomes.

Habitat

Bogs, brackish or salt marshes and flats, floodplain (river or stream floodplains), marshes, shores of rivers or lakes, wetland margins (edges of wetlands)

Characteristics

Habitat
  • aquatic
  • wetlands
New England state
  • Connecticut
  • Maine
  • Massachusetts
  • New Hampshire
  • Rhode Island
  • Vermont
Stem shape in cross-section
the stem is round or oval in cross-section
Leaf blade width
0 mm
Leaf blade cross-section
NA
Inflorescence position
the inflorescence is at the tip of the plant
Inflorescence branching
the inflorescence is on one or more stems with no branches
Fruit type (general)
the fruit is like a seed, and surrounded by scales
Fruit length
0.5–1.1 mm
Leaf position on plant
the attachment points of all the leaves are at or near the base of the plant
Perianth composition
  • there are bristles attached at the base of the achene
  • there is no perianth on the plant
Fruit cross-section
  • the fruit is biconvex or elliptic (widest in the middle and tapering to both ends) in cross-section
  • the fruit is triangular to terete (circular) in cross-section
Show All Characteristics
  • Flowers
    Anther length
    0.7–1 mm
    Floral bristle color
    the bristles are white
    Floral bristle number
    • 0
    • 1-4
    • 5-7
    • 8 or more
    Floral bristle relative length
    the bristles are longer than the achene
    Floral bristles
    the bristles are straight or slightly curved
    Floral scale hairs
    there are no hairs on the floral scales
    Floral scale length
    1–3 mm
    Floral scale nerves
    0
    Floral scale shape
    the floral scales are elliptic (widest in the middle and tapering toward each end)
    Floral scale translucent
    the floral scales are opaque
    Inflorescence bract angle
    NA
    Inflorescence bract number
    NA
    Inflorescence bract position (Sparganium)
    NA
    Inflorescence bracts
    NA
    Inflorescence branching
    the inflorescence is on one or more stems with no branches
    Inflorescence crowding
    • NA
    • the inflorescence is crowded together in one tight cluster
    Inflorescence position
    the inflorescence is at the tip of the plant
    Inflorescence shape
    the aggregations within the inflorescence are roughly circular (not flattened) in cross-section
    Inflorescence type
    there is one spike or raceme at the tip of the stem
    Perianth composition
    • there are bristles attached at the base of the achene
    • there is no perianth on the plant
    Stamen number
    • 1
    • 2
    • 3
    Stigma number
    2
    Style division
    the top two thirds of the style is divided
    floral bristle barbs
    the bristles have tiny barbs on them
    plantlets budding at flower bases
    • no
    • yes
  • Fruits or seeds
    Achene beak length
    0 mm
    Achene surface texture
    the achene has very tiny pits or depressions on it
    Achene tubercle relative width
    the tubercle is one half or less as wide as the achene
    Achene tubercle width
    0.2–0.4 mm
    Capsule relative length
    NA
    Fruit cross-section
    • the fruit is biconvex or elliptic (widest in the middle and tapering to both ends) in cross-section
    • the fruit is triangular to terete (circular) in cross-section
    Fruit length
    0.5–1.1 mm
    Fruit type (general)
    the fruit is like a seed, and surrounded by scales
    Fruit type (specific)
    the fruit is an achene (dry, seed-like fruit) with a tubercle (a swelling or projection, usually of a different color or texture) on it
    Locules in capsule
    NA
    Seed length
    0 mm
    Seed tail relative length
    0 mm
    Seed tails
    NA
    Tubercle height
    0.3–0.7 mm
  • Growth form
    Lifespan
    the plant lives more than two years
    Rhizome thickness
    0.5–1 mm
    Underground organs
    the plant has a rhizome (a horizontal underground stem with roots growing from it)
  • Leaves
    Auricle length
    0 mm
    Auricle texture
    NA
    Auricles
    there are no auricles on the leaf sheath
    Leaf blade cross-section
    NA
    Leaf blade length
    0 mm
    Leaf blade width
    0 mm
    Leaf form
    all the leaves hold their form out of water
    Leaf position on plant
    the attachment points of all the leaves are at or near the base of the plant
    Leaf septa
    NA
    Leaf sheath hairs
    the leaf sheathes are without hairs
    Pedicel length (Typha)
    0 mm
    Stem leaf blade ligules
    NA
    Stem leaf blades
    there are no leaves on the main stem, or there is a small tooth or tiny blade, or a leaf sheath with no blade
    Width of seed-producing inflorescence
    1–2 mm
  • Place
    Habitat
    • aquatic
    • wetlands
    New England state
    • Connecticut
    • Maine
    • Massachusetts
    • New Hampshire
    • Rhode Island
    • Vermont
    Specific habitat
    • bogs
    • brackish or salt marshes and flats
    • edges of wetlands
    • marshes
    • river or stream floodplains
    • shores of rivers or lakes
  • Stem, shoot, branch
    Plant height
    3–28 cm
    Stem shape in cross-section
    the stem is round or oval in cross-section
    Stem texture near tip
    the stem feels smooth near the tip
    Stem thickness at midpoint
    0.3–0.6 mm

Wetland Status

Occurs only in wetlands. (Wetland indicator code: OBL)

New England Distribution and Conservation Status

Distribution

Connecticut
present
Maine
present
Massachusetts
present
New Hampshire
present
Rhode Island
present
Vermont
present

Conservation Status

Exact status definitions can vary from state to state. For details, please check with your state.

var. olivacea

Vermont
extremely rare (S-rank: S1)

Native to North America?

Yes

Sometimes Confused With

Eleocharis intermedia:
styles trifid, achenes compressed-trigonous, and leaf sheaths variable at apex, but without a prolonged white, scarious apex (vs. E. flavescens, with styles usually bifid, achenes biconvex, and leaf sheaths prolonged at summit into a white, scarious tip).

Synonyms

  • Eleocharis olivacea Torr.

Family

Cyperaceae

Genus

Eleocharis

Notes on Subspecies and Varieties in New England

Our variety is Eleocharis flavescens (Poir.) Urban var. olivacea (Torr.) Gleason.

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Information from Dichotomous Key of Flora Novae Angliae

11.  Eleocharis flavescens (Poir.) Urban var. olivacea (Torr.) Gleason N

yellow spikesedge. Eleocharis olivacea Torr. • CT, MA, ME, NH, RI, VT. Shorelines, marshes, tidal river shores, peatlands.